The 2-0 defeat represented the first time Everton have conceded more than once at Goodison Park since Allardyce took charge in late November.
"We have many good players at the Club, so I was waiting for my chance and I knew I'd get that because there are many games, especially in this period," said 20-year-old Vlasic.
“I will always continue to work hard and hope for my chances to impress. Every player needs to show their best in training in order to get into the manager's team for the games.
“Before [Allardyce was appointed] we had really bad results but the new manager has come in and we got some good results. Now after this we need to go back to training, work hard and put things right."